Radio frequency (RF) communication, including point-to-point RF communication, is well known.
For outside broadcasting applications, there are many scenarios where multiple communication units, each coupled to a respective television camera, are required to transmit video data to a central production communication unit (and sometimes operate bi-directionally, i.e. also receive video data transmitted by the central production communication unit).
It is known that transmissions in a frequency band of 57 to 64 GHz located around 60 GHz undergo strong atmospheric absorption, and that in the UK and other countries these frequencies form an “unlicensed band”. The equipment however has to conform to the relevant regulatory technical specifications to ensure that interference is not provided to those operating within adjacent licensed bands. This frequency band is also potentially attractive for point-to-point communication due to the strong atmospheric absorption limiting interference from other signals. However, such characteristics also would conventionally lead to difficulties in achieving desired transmission distances for e.g. outside broadcast applications, especially if modulation, transmission and reception apparatus is desired to be relatively small in size for reasons of portability and so on. This difficulty is exacerbated by increasing video data rates, e.g. if it were desired to perform point-to-point transmission of uncompressed High Definition (HD) Serial Digital Interface (SDI) video signals (1.485 gigabits/second).
For example, conventional transmitter modules and receiver modules for interfacing transmitter and receiver integrated circuits (i.e. chips) and other elements, using discrete waveguide connections and the like, with commensurate stringent electromagnetic separation requirements at 60 GHz, tend to be bulky and cumbersome.
Also, with regard to achieving relatively long range performance (e.g. >1 km), conventional analogue modem designs typically limit performance when operating in a channel suffering from fading. An all digital modem solution may offer better performance but would have a number of disadvantages in terms of size, weight, power consumption and cost.